FGL2-targeting T cells exhibit antitumor effects on glioblastoma and recruit tumor-specific brain-resident memory T cells

Although tissue-resident memory T (TRM) cells specific for previously encountered pathogens have been characterized, the induction and recruitment of brain TRM cells following immune therapy has not been observed in the context of glioblastoma. Here, we show that T cells expressing fibrinogen-like 2 (FGL2)–specific single-chain variable fragments (T-αFGL2) can induce tumor-specific CD8+ TRM cells that prevent glioblastoma recurrence. These CD8+ TRM cells display a highly expanded T cell receptor repertoire distinct from that found in peripheral tissue. When adoptively transferred to the brains of either immunocompetent or T cell-deficient naïve mice, these CD8+ TRM cells reject glioma cells. Mechanistically, T-αFGL2 cell treatment increased the number of CD69+CD8+ brain-resident memory T cells in tumor-bearing mice via a CXCL9/10 and CXCR3 chemokine axis. These findings suggest that tumor-specific brain-resident CD8+ TRM cells may have promising implications for the prevention of brain tumor recurrence.


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We require information from authors about some types of materials, experimental systems and methods used in many studies. Here, indicate whether each material, system or method listed is relevant to your study. If you are not sure if a list item applies to your research, read the appropriate section before selecting a response. For in vivo and in vitro studies, sample sizes were decided based on the similar studies reported in the previous literature. Given 3-9 repeated or mice per group, we have 80% power to detect a difference in means between two groups at a significance level of 0.05 using two-sample t-test.
The data of outlier point, which was further than 1.5*interquartile Range away from the mean, was excluded.
In vivo experiment was conducted at least twice at different times. For in vitro experiment, replicates were not less than three in each group. All the replications showed the similar results. mice at same age and same gender with similar tumor burden were randomly grouped into different treatment.
Mice in different groups were received different treatment performed by us. But the survival time was determined by the moribund condition which was assessed by staff works in Department of Veterinary Medicine and Surgery, who didn't know the group information of the mice ( so it's single-blinded).

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Flow Cytometry
Plots Confirm that: The axis labels state the marker and fluorochrome used (e.g. CD4-FITC).
The axis scales are clearly visible. Include numbers along axes only for bottom left plot of group (a 'group' is an analysis of identical markers).
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DBT mouse glioma cells were kindly provided by Dr. Leonid Metelitsa (Baylor College of Medicine). GL261 cells were obtained from the National Cancer Institute. 4T1 cells were purchased from ATCC.
Cells were collected for DNA isolation, and further gene fingerprint authentication.
All cells were treated with mycoplasma removal agent (Bio-Red) for one week and tested negative for mycoplasma contamination before use.
No commonly misidentified cell lines were used in the study We purchased Balb/c, C57BL/6 (5-8 weeks of age), B6.129P2-Cxcr3tm1Dgen/J, and Thy1.1 (CD90.1+) mice from The Jackson Laboratory. Fc%RIIB-/-mice (Fcgr2b-Model 579) were purchased from Taconic. FGL2$/$ mice were a gift from Dr. Gary Levy (Toronto General Hospital/Research Institute), and NOD.CB17-Prkdcscid/J (SCID) mice were a gift from Dr. Richard Gorlick (The University of Texas MD Anderson Cancer Center). All mice were aged 6 to 12 weeks when the experimental procedures began. Both gender were used in experiments.
The study didn't use wild animals.
The study did not involve samples collected from field.
We performed all animal experiments in accordance with the guidelines approved by the Institutional Animal Care and Use Committee (IACUC) at MD Anderson.
The tumor tissue sections used in this study were from newly diagnosed primary GBM patients.
Sample collection was conducted under protocol #LAB03-0687, which was approved by the Institutional Review Board of The University of Texas MD Anderson Cancer Center, after written informed consent was obtained. Patients' tumors were graded by a neuropathologist according to the World Health Organization classification.
The Institutional Review Board of The University of Texas MD Anderson Cancer Center Mouse brain tissues and LNs were minced and enzymatically digested to obtain single-cell suspensions. BILs were isolated per